Crimping machine



y 8, 1963 c. R. MENTZER 3,091,275

CRIMPING MACHINE Filed Jan. 27, 1960 e Sheets-Sheet 1 INVENTOR. CHARLESR. HENuER May 28, 1963 c. R. MENTZER 3,

CRIMPING MACHINE Filed Jan. 27, 1960 s Sheets-Sheet 2 INVENTOR. CHARLESR. NENTZER y 8, 1963 c. R. MENTZER 3,091,275

CRIMPING MACHINE Filed Jan. 27. 1960 6 Sheets-Sheet 3 4 INVENTOR.

E 1; CHARLES R. NENTZER y 8, 1963 c. R. MENTZER 3,091,275

CRIMPING MACHINE Filed Jan. 27, 1960 6 Sheets-Sheet 4 INVENTOR. CHARLESR. NENTZER m ym im May 28, 1963 Filed Jan. 2'7, 1960 C. R. MENTZERCRIMPING MACHINE 6 Sheets-Sheet 5 INVENTOR. CHARLES R. MENTZER M W M May28, 1963 c. R. MENTZER CRIMPING MACHINE 6 Sheets-Sheet 6 Filed Jan. 27,1960 INVENTOR. Camus RMENTZER 3,091,275 CRIMPING MACIWE Charles R.Mentzer, Harrisburg, Pa., assignor to All 1P Incorporated, Harrisburg,Pa. Filed Jan. 27, 1960, Ser. No. 5,044 Claims. (Cl. 153-1) Thisinvention relates to machines for crimping connectors or terminals ontothe ends of wires.

An object of the invention is to provide an improved apparatus forfeeding a succession of terminals or connectors to a crimping stationand crimping the leading.

connector onto a wire. A further object is to provide a crimpingapparatus having an improved wire stripping and positioning means. Astill further object is to provide a crimping apparatus which isparticularly adapted to apply relatively small connectors onto extremelysmall diameter conductors. A still further object is to provide animproved apparatus for crimping open-U type connectors and having meansfor bending the sides of the connector inwardly and for subsequentlycrimping the connector by application of a compressive force to theinwardly bent sides.

These and other objects are achieved in a preferred embodiment of theinvention comprising a bell crank lever pivoted at its apex and having acrimping die secured to the end of one of its arms. The other arm of thebell crank has a resilient connection with a reciprocable rod so that asthe rod moves in a first direction, the crimping die is moved relativelytowards a fixed crimping anvil. Mounted on each side of the bell crankby means of a lost motion connection are a pair of levers having bendingarms on their ends. These bending arms, upon arrival at the crimpingdie, are adapted to move relatively towards each other thereby to bendthe upstanding sidewalls of a U-shaped connector inwardly and to foldthese sidewalls over a wire disposed within the connector. The bendingarms of these levers then move apart and the crimping die descends andapplies a compressive force to the connector to complete the crimpingoperation. The preferred embodiment is adapted to feed and to crimpconnectors in strip form and to this end provides a feeding meansactuated by the above mentioned reciprocaole rod so that a singleconnector, the leading connector of a strip, is fed to the crimpinganvil during each cycle of operation. In order to shear this leadingconnector from the strip and to trim the wire portion which extendsbeyond the connector after crimping, there are provided shears movablein planes adjacent the crimping anvil and actuated by the Ieciprocablerod which actuates the bell crank. In order to strip the end of the wirethere are provided a pair of abrasive wheels adjacent the crimping anvilso that when the operator positions the Wire in the uncrimped terminalwith its end extending beyond the connector, the end is caught in thesewheels and the insnlation removed therefrom. The operator can thenwithdraw a portion of the wire from the wheels so that a strippedsection thereof rests within the connector and this stripped section iscrimped and held by the connector.

In the drawing:

FIGURE 1 is a perspective view of a preferred embodiment of theinvention;

FIGURE Q is a perspective view showing a strip of connectors and showinga crimped connector on the ends of a pair of wires;

FIGURE 3 is a perspective view showing a bell crank lever and a crimpingmeans thereon and the pneumatic piston-cylinder which actuates the bellcrank which forms part of the preferred embodiment;

FIGURE 4 is a sectional view showing the preferred embodiment at thebeginning of a crimping cycle;

$391,275 Patented May 28, 1963 FIGURES 5 and 6 are views similar toFIGURE 4 but showing the progressive stages of the crimping cycle andillustrating the movement of the parts during the cycle;

FIGURES 7, 8, 9 and 10 are frontal views of the crimping die and thebending arms and illustrating the relative positions of these partsduring the crimping cycle;

FIGURE 11 is a frontal view showing the feed mechanism and the crimpingarea;

FIGURE 11A is a view taken along the line 11-41 of FIGURE 11;

FIGURE 12 is a view taken along the line 12-12 of FIGURE 11;

FIGURE 13 is a perspective view showing the strip shearing means and thewire shearing means;

FIGURE 14 is a fragmentary perspective view showing the actuatinglinkage for the two shearing means; and

FIGURE 15 is a view taken along the lines 15--15 of FIGURE 5.

The disclosed embodiment of the invention is adapted to crimp connectorsin strip form as shown in in FIGURE 2 onto the ends of wires. The stripof FIGURE 2 comprises a tape of plastic material 86, such as Mylar(polyethyleneterephthalate) to which connectors 88 are attached, as byan adhesive, at regularly spaced intervals. The particular connectordisclosed is a simple trough-like open-U terminal having one of itssidewalls relatively higher than the other sidewall and is particularlyintended to join an extremely fine (e.g. 0.002" diameter) coil wire to alead wire which is relatively much 'heavier. In use, the two wires areplaced within the connector and the sidewalls are folded over each otherand crimped. Thereafter, the plastic tape is cut and, in the case ofconnections between coil wires and lead wires, the tape is positionedagainst the coil. The cut section of tape with the crimped connectionthereon is then secured to the coil by means of an additional piece ofadhesive tape.

The preferred embodiment of the invention is mounted in a framecomp-rising a base 2 having a pair of parallel spaced apart webs orflanges 4, 6 which support a top plate 8. This top plate does not restdirectly on the tops of the webs but is hinged thereto as shown at '10and is resiliently urged downwardly in the front portion of the machineagainst a stop 14 by means of a coil spring 12. It will be understoodthat a counterpart hinge to the hinge 10 is provided on the oppositeside of the machine from the side shown in FIGURE 1. Top plate 8 is cutaway as shown at 16 and a bell crank 18 is positioned in this cut awaysection and between the webs 4, 6. This bell crank is pivotally mountedat its apex on a pin 20 which is supported by ears 22 which extend froma support block 24 (FIGURE 3) contained between and secured to the webs4, 6.

A first arm 26 of the bell crank has a crimping die 28 secured to itsend and a second arm 30 has an enlarged end 32 through which passes arod extension 33 of a piston rod 34 which, in turn, extends from apneumatic piston cylinder 36. The end of arm 36 of the bell crank isheld between a bar 38 'on piston rod extension 33 and a washer 40. Thiswasher is resiliently biased against bar 38 by means of a coil spring42, on the end of the rod extension which is retained in place by a nut'44. This arrangement permits the rod 34 and extension 33 .to moverightwardly during a portion of its stroke independently of bell crankarm 30 as is explained below. In order to prevent rightward orcounterclockwise movement of the :arm 3% beyond the desired point, thereis provided a stop 46 on the base 2 which is adjustably clamped by meansof a fastener 43 extending through the :base and into a threaded openingin the stop block. An adjusting screw 50 extends through the front plateof the apparatus and into a threaded opening in the stop block 46. This3 adjusting screw is threaded through the front plate at 52 so that uponloosening of fastener 48 and rotation of screw 52, the stop can beadjusted towards and away from the front of the apparatus thereby tovary the stroke of the bell crank.

A pair of bending arms 56 are disposed on each side of crimping die 28and are secured at their upper ends to the ends of levers 58. Theselevers are clamped intermediate their ends against flat surfaces 62 onthe opposite sides of the bell crank by means of spring washers 63 and abolt 64 which extends through circular openings in the levers and anarcuate slot 66 in the bell crank. This arrangement permits 'abothrelative motion oat the bell crank with respect to the levers andmovement of thebell crank independently of the levers. The leversadditionally are pivotally mounted on pin 20 and have end portions 61which extend rearwardly beyond the bell crank and are secured to a block60 so that they move in unison. A stop 68, which is adapted to contactblock 60 and prevent counterclockwise motion of the levers beyond apredetermined point, is supported by means of a U-shaped bracket 70which is secured to the webs 4, 6 of the (frame. An additional stop 72is provided to prevent clockwise motion of the levers beyond apredetermined point and this stop is engaged by an adjustable screw 73which extends through block 69. Stop 72 in turn is supported on a crossbar 74 which is secured to the support block 24.

As best shown in FIGURE 7, the bending arms extend parallel to the sidesof the crimping die and are inwardly directed at 80. These arms normallyextend beyond the crimping die and have lower parallel extensions 81inwardly curved at their tips :as shown at 32 and having heels 3.3 tolimit their movement towards each other. In use, these arms are requiredto move relatively towards each other during counterclockwise motion ofthe bell crank in order to :bend the sidewalls of the terminal inwardly.To this end the levers themselves have a resilient bias inwardly towardsthe bell crank but are held in the positions shown in FIGURE 7 by virtueof screws 78 in the levers which bear against the opposite sides of thecrimping die. Recesses 76, which function as camming surfaces, areprovided on the sides of the crimping Edie which are opposed to thelevers. As the bell crank rotates, block 60 contacts stop 68 and furthermovement of the levers and bending arms towards the anvil is prevented.Thereafter, the bell crank continues to move in a counterclockwisedirection as viewed in FIGURE 4 and the crimping die moves downwardlytowards the interval relative to the levers. During this dwell of thelevers, the screws 78 move into recesses 76 as shown in FIGURES 7 and 8,and the ends 81 of the bending arms also move inwardly towards eachother to bend the sidewalls of the terminal towards each other. Uponfurther movement of the crimping die, the bending arms are cammed apartby the cam surfaces 76 of the crimping die so that crimping die can bepressed against the terminal to complete the crimp. It will beunderstood that the levers 58 should be clamped by the spring washers 63against the flat surfaces 62 on the bell crank with sufii cient force toensure the movement of the levers and the bell crank as a unit duringthe initial stages of the stroke, however, the clamping pressure shouldnot be unduly high in order to permit the relative motion, shown inFIGURES 7-10, between the levers and the bell crank.

Referring now to FIGURES 1, 11 and 12, the feed mechanism for feedingthe terminal strip comprises a feed finger 90 which is adapted to pushthe strip from a source (not specifically shown) along a channel 84 onthe upper edge of the front plate 54 of the machine frame. This fingeris pivoted at 92 to one arm 96 of a bell crank lever and has a torsionspring 94 fitted into a slot in its base which normally biases thefinger in a clockwise direction as viewed in FIGURE 11. The bell crankto which the finger is attached is pivotally mounted at 98 on a pinwhich in turn is mounted in front of plate 54. The other arm 1% of thebell crank is normally biased downwardly in FIGURE 11 by means of a coilspring 102 secured at its end to the base of the machine fname. The apexof the bell crank provides a flat face to which is secured a leaf spring104, the end of which is engaged by a cm 166 mounted rotatably on a pin133 extending from the base 2 of the frame. As shown in FIGURE 12, uponclockwise movement of this cam 1%, the end of the leaf spring 194 willbe moved leftwardly in FIGURE 11 resulting in clock-wise motion of thebell crank 0n pivotal axis 98. This motion imparts a rightward movementto feed finger to feed the strip of terminals rightwardly towards thecrimping anvil. Cam M96 is actuated by means of a bar secured to anextension 112 on the previously mentioned bar 33. It will thus beapparent that upon motion of the piston rod towards the front of theapparatus and leftwardly in FIGURE 4, the cam 106 will be rotated in aclockwise direction and this will cause clockwise movement of the bellcrank and rightward movement of the feed finger. On the return stroke ofthe piston rod 34, spring 102 is effective to cause counterclockwisemotion of the bell crank and retract the feed finger so that it will bepositioned behind the next adjacent terminal on the strip to feed thisnext terminal to the crimping anvil at the end of the forward stroke.

The length of the stroke of the feed finger can be adjusted by means ofstop screws 113 threaded through the opposite sides of channel 114. Asshown best in FIG- URE 11A, bell crank arm 96 comes to rest againstthese stops at the limits of its stroke in both directions. It should beadded that the leaf spring 104 on the bell crank renders it unnecessaryto adjust the position of cam 106 when the stroke is changed. If thiscam overtravels (continues to rotate after the edge of the bell crankarm comes to rest against the righthand stop 113 in FIGURE 11A), theleaf spring will merely be resiliently stressed to a slight extent.

It is desirable to provide some type of hold down device for lightlypressing the strip of terminals into the channel shaped feed path on theupper face of the front plate 54. To this end, there is provided anL-shaped bracket secured to channel 114 and having a leaf spring 122 onits end which extends downwardly toward the terminal feed path andparallel to the path as shown in FIGURE 11.

A shear, for shearing the strip of plastic material 86 V at a pointadjacent the crimping anvil, is provided in the form of a shear blade124 having an opening in its end through which the strip is adapted topass. This shear blade extends through a slot in the front plate and ismounted on a slide member 126 which is held against a bracket 128 on thefront plate of the frame, the face of the front plate being recessed forthe accommodation of this slide. The slide is reciprocated by means of alever 130 (FIGURE 14) which in turn is secured to a rod 134 extendingparallel to, and in back of, the front plate. Rod 134 has a clampingblock 136 on its end which is slotted at 138 for the reception of theflattened end 140 of a control rod 142 to which it is pivotallyconnected. Control rod 142 is slidably supported in bearing blocks 144on the outside surface of web 4 to permit motion'parallel to the motionof the piston rod 34. Rod 142 is retracted during the last portion ofthe rightward stroke of the piston rod as viewed in FIGURE 4 by means ofan arm or extension 145 on plate 38-. This plate engages a collar 147secured to the rod 142 and pushes it rightwardly, during the finalstages of the stroke, against the compression of a spring 149 interposedbetween the one bearing block 144 and the collar 147. It will beappreciated that only a very slight amount of movement of this rod isneeded to actuate the shear 124.

Advantageously, means are provided to trim the portion of the wire whichextends beyond the terminal after it has been crimped. In the preferredembodiment such means is provided in the form of a wire shear 152 whichextends through a slot in the front plate and is disposed within therecess in the front plate. This wire shear is secured at its end to ahub 152 pivotally mounted on a pin 153 and has an arm 154- extendingdownwardly therefrom and leftwardly as viewed in 13. This arm is slottedat its end for the accommodation of a cam follower 156 which is adaptedto be engaged by a cam 15% on blade holder 126. A leaf spring 16%mounted on support 129 normally biases -arm 154 in a clockwise directionas viewed in FIGURE 13 but permits counterclockwise motion of the arm.Thus, upon downward motion of the blade holder 126, hub 152 is rotatedin a counterclockwise direction against the force of spring 160 and theshearing edge of the blade 152 passes relatively downwardly into theslot through which it extends and severs the end of the wire.

Extremely fine wires on which the instant machine is adapted to operateare frequently coated with a varnish type insulation which must beremoved in the vicinity of the crimp, and these wires are difficult toposition within the terminal, particularly if the terminal is relativelysmall as in the instant circumstances. In order to both strip andposition the wire, there is provided a pair of stripping wheels 162, 164in front of the bell crank and directly behind the anvil portion of thechannel 84. These stripping wheels are mounted on the ends of shafts166, 168 which are rotatably supported in blocks 170, 172. Block 170 ispivoted at its rearward end to block 172 and the two blocks are heldapart as shown in FIGURE 1 by the wheels themselves. Thus as the wheelsprogressively wear down in use, the block 17% moves downwardly relativeto the block 172 to maintain the spacing between the wheels. It shouldbe added at this point that the purpose of providing a hinged mountingfor the upper plate 8 is to permit adjustment of this plate so that thewheels will be positioned with their line [of tangency in the plane ofthe crimping anvil. A pulley 176 on the end of shaft 168 is connected bymeans of a belt 178 to the pulley 18% on the end of a shaft extendingfrom a motor 182 so that these wheels are continuously rotated duringuse. It will be apparent that the upper one of the wheels is turned onlyby virtue of its frictional contact with the lower wheel although ifdesired, a direct drive for both of these stripping wheels can beprovided.

The stripping wheels 162, 164- may be of any desired type suitable forthe wire being used. One type of stripping wheel which is particularlyadapted for extremely fine wire is composed of a plurality of fibreglass discs, each disc being made up of a plurality of radiallyextending strands. Stripping wheels of this type will remove all of thevarnish type insulation on an extremely fine wire without damaging thewire itself.

In use, the operator will generally wish to strip the end of anextremely fine wire and crimp this fine wire along with a relativelylarger diameter lead wire in a terminal. To accomplish this, theoperator first inserts the end of the fine wire over the anvil portionof the front plate until its end is engaged by the stripping wheels.These wheels tend to draw the wire inwardly of the machine and in doingso will remove the varnish type insulation. It is necessary for theoperator to feed a length of fine wire sufficient to extend from theline of tangency of the wheels to the terminal positioned on the anvil.After this length of wire has been drawn between the wheels, theoperator withdraws the fine wire by pulling on it until a strippedportion is positioned over the uncrimped terminal on the anvil. It is anadvantage that during the entire operation this extremely fine wire isheld taut by the wheels thereby facilitating the operation ofpositioning it relatively over the uncrimped terminal. After the wirehas been stripped and positioned over the terminal in this manner, thesecond wire, usually a larger diameter lead wire, is positioned 6.within the terminal and the operator actuates the pneumatic pistoncylinder. Thereafter, the piston rod moves rightwardly as viewed inFIGURE 4 and the bell crank is rotated in a counterclockwise direction.The bending arms move downwardly and then inwardly as the sequence ofoperation shown in FIGURES 7-9 is followed and the upstanding sidewallsof the terminal are bent partially inwardly towards each other. Afterthis inward bending of the sidewalls, the arms move outwardly again andthe crimping die presses the terminal against the anvil to firmly setthese sidewalls and secure the terminal onto the wire end. After theterminal has been crimped, and the end of the bell crank has come torest against stop 46, the piston rod 34 continues to move rightwardlyand is permitted to .do so by virtue of the resilient coupling 42, 4%)between the arm of the bell crank and the piston rod. During this finalportion of the rightward stroke, the rod 142 is moved rightwardlythereby to actuate the Wire shear and the strip shear. During thisperiod the wire will be held by the abrasive wheels so that it can besheared in a precise location relative to the strip. After the pistonrod 34 reaches the end of its rightward stroke it immediately returnsand causes the bell crank to rotate in a clockwise direction thusraising the crimping and the bending arms. During this reverse stroke,the stop 72 is effective to prevent movement of the levers 61, 58 beyonda predetermined position and the crimping die moves relatively upwardlywith respect to the pin 76 (FIGURE 7). As a result the bending arms andthe crimping die at the end of the stroke are positioned in a relativeposition shown in FIGURE 7. During the final portion of the forwardstroke of the ram, cam- 106 (FIGURE 12) is rotated as described above tofeed the next adjacent terminal up to the crimping anvil area of thefront plate.

The salient overall advantage of the invention is that it isparticularly adapted to crimp extremely small connectors onto the endsof extremely fine wires which can not be handled by the heretofore knowntypes of crimping devices. Several features of the invention contributeto the ability of this preferred embodiment to handle such wires. Asmentioned above, the abrasive Wheels hold the wire so that it can beprecisely positioned relative to the terminal, an operation which wouldotherwise be extremely difiicult because of the delicacy of the wiresand the small size of the uncrimped connectors. The preferred embodimentis also adapated to feed and to shear terminals of the particular typeshown in FIGURE 2 which are extremely small and are secured to a plasticstrip. The shearing means operates while the terminal is clampedsecurely by the crimping die and the crimping ram on the end of the bellcrank provides means to bend the sides of the terminal inwardly as wellas to crimp the sides after they have been partially bent together. Itwill be appreciated that the extremely small terminals required for finewires can not be bent inwardly and downwardly by a single die as iscommon practice with terminals for larger sized wires.

Changes in construction will occur to those skilled in the art andvarious apparently different modifications and embodiments may be madewithout departing from the scope of the invention. The matter set forthin the foregoing description and accompanying drawings is offered by wayof illustration only. The actual scope of the invention is intended tohe defined in the following claims when viewed in their properperspective against the prior art.

I claim:

1. Apparatus for crimping open-U type electrical terminals in strip formonto wires, said apparatus comprising. an anvil, means for feeding asuccession of terminals in strip form to said anvil, a bell crankpivotally mounted at its apex, at crimping die on one arm of said bellcrank whereby upon rotary motion of said bell crank said crimping die ismoved relatively towards and away from said anvil, a strip shearingblade disposed adjacent said anvil and movable in a plane extendingtransversely of the plane of said strip and past said strip at alocation between the leading terminal of said strip on said anvil andthe next adjacent terminal to sever said leading terminal from saidstrip, actuating linkage for said blade, a reciprocable rod, lost motionmeans for engaging said rod with said actuating linkage during theterminal portion of the stroke of said rod in one direction, a resilientconnection between said rod and the other arm of said bell crank, and astop for said bell crank arm to prevent movement thereof after crimpingof saidterminal whereby, upon movement of said rod in said one directionsaid bell crank is first rotated to crimp said terminal, and said stripshearing blade is then actuated while said crimping die dwells to seversaid strip.

2. Apparatus for crimping open-U type terminals in strip formcomprising, a bell crank pivotally mounted at its apex, a crimping diemounted on one arm of said bell crank, a fixed crimping anvil orcooperation with said crimping die, means for feeding a succession ofterminals in strip form to said anvil, a shear disposed adjacent saidanvil for shearing the leading terminal from said strip, a reciprocablerod, said rod being resiliently coupled to the other arm of said bellcrank whereby upon movement of said rod in a first direction, said bellcrank is rotated and said crimping die is moved relatively towards saidanvil, a stop for said bell crank to prevent movement of said crimpingdie beyond a predetermined position relative to said anvil whilepermitting continued movement of said rod in said first direction aftersaid bell crank has come to rest against said stop, and means actingbetween said terminal feeding means and said rod for actuating saidterminal feed means during return movement of said rod in a directionopposite to said first direction.

3. Apparatus for crimping open-U type terminals in strip form comprisinga bell crank pivotally mounted at its apex, a crimping die mounted onone arm of said bell crank, a fixed crimping anvil for cooperation withsaid crimping die, means for feeding a succession of terminals in stripform to said anvil, a strip shear disposed adjacent said anvil forshearing the leading terminal from said strip, a Wire shear disposedadjacent said anvil for shearing excess wire extending from saidterminal, a reciprocable rod, said rod being resiliently coupled to theother arm of said bell crank whereby upon movement of said rod in afirst direction, said bell crank is rotated and said crimping die ismoved relatively towards said anvil, a stop for said bell crank toprevent movement of said crimping die beyond a pre determined positionrelative to said anvil While permitting continued movement of said rodin said first direction, means acting between said rod and both of saidshears 'for actuating said shears during movement of said rod in a firstdirection after said bell crank has come to rest against said stop, andmeans acting between said terminal feed means and said rod for actuatingsaid terminal feed means during return movement of said rod in adirection opposite to said first direction.

4. Crimping apparatus for crimping open-U type connectors comprising, afixed anvil, a crimping die movable relatively towards and away fromsaid anvil, a pair of bending arms disposed on opposite sides of saidcrimping die and having tip portions normally extending beyond said dietowards said anvil, portions of said arms being held frictionallyagainst the sides of said crimping die whereby said arms are normallymovable with said die but said die is movable relative to said arms whensaid arms are held against movement, said arms being resiliently biasedinwardly towards said die, stop means for preventing movement of saidarms during a terminal portion of the stroke of said die towards saidanvil, and camming means acting between said die and said arms, saidcamming means functioning to permit said arms to move by virtue of theirresilient tendencies, relatively inwardly and their tips to moverelatively towards each other during said terminal portion of saidstroke, and said camming means causing said arms subsequently to moveapart whereby, during said stroke, said bending arms bend the sidewallsof said terminal inwardly, and said crimping die thereafter bends saidsidewalls downwardly Ito crimp said terminal onto a wire.

5. Crimping apparatus for crimping open-U type connectors comprising, afixed anvil, 'a crimping die movable relatively towards and away fromsaid anvil, a pair of bending arms carried by, and disposed on oppositesides of, said crimping die, said die being movable relative to saidarms upon application of a holding force to said arms, said armsnormally extending beyond said crimping die and being resiliently biasedinwardly towards said die, means for applying a :holding force to saidarms during a terminal portion of the stroke of said die towards saidanvil, and cam means for permitting said arms to move inwardly towardseach other and for subsequently moving said arms apart during saidterminal portion of said stroke whereby said bending arms inwardly bendthe sidewalls of a terminal positioned on said anvil and said diethereafter bends said arms downwardly over the base of said terminal.

References Cited in the file of this patent UNITED STATES PATENTS

4. CRIMPING APPARATUS FOR CRIMPING OPEN-U TYPE CONNECTORS COMPRISING, AFIXED ANVIL, A CRIMPING DIE MOVABLE RELATIVELY TOWARDS AND AWAY FROMSAID ANVIL, A PAIR OF BENDING ARMS DISPOSED ON OPPOSITE SIDES OF SAIDCRIMPING DIE AND HAVING TIP PORTIONS NORMALLY EXTENDING BEYOND SAID DIETOWARDS SAID ANVIL, PORTIONS OF SAID ARMS BEING HELD FRICTIONALLYAGAINST THE SIDES OF SAID CRIMPING DIE WHEREBY SAID ARMS ARE NORMALLYMOVABLE WITH SAID DIE BUT SAID DIE IS MOVABLE RELATIVE TO SAID ARMS WHENSAID ARMS ARE HELD AGAINST MOVEMENT, SAID ARMS BEING RESILIENTLY BIASEDINWARDLY TOWARDS SAID DIE, STOP MEANS FOR PREVENTING MOVEMENT OF SAIDARMS DURING A TERMINAL PORTION OF THE STROKE OF SAID DIE TOWARDS SAIDANVIL, AND CAMMING MEANS ACTING BETWEEN SAID DIE AND SAID ARMS, SAIDCAMMING MEANS FUNCTIONING TO PERMIT SAID ARMS TO MOVE BY VIRTUE OF THEIRRESILIENT TENDENCIES, RELATIVELY INWARDLY AND THEIR TIPS TO MOVERELATIVELY TOWARDS EACH OTHER DURING SAID TERMINAL PORTION OF SAIDSTROKE, AND SAID CAMMING MEANS CAUSING SAID ARMS SUBSEQUENTLY TO MOVEAPART WHEREBY, DURING SAID STROKE, SAID BENDING ARMS BEND THE SIDEWALLSOF SAID TERMINALS INWARDLY, AND SAID CRIMPING DIE THEREAFTER BENDS SAIDSIDEWALLS DOWNWARDLY TO CRIMP SAID TERMINAL ONTO A WIRE.